1. Field of the Invention
This invention relates to lithography. In one aspect, the invention relates to a method of producing multidimensional lithographic separations while in another aspect, the invention relates to a method of producing such separations free of moire interference. In yet another aspect, the invention relates to producing lithographic motion pictures.
2. Description of the Related Art
Lithography is an old, well-known and well-practiced art. In its first life, lithographs were created by drawing on the surface of a limestone slab with an oily wash or greasy crayon. The surface was then washed with an acid such that the marked areas of the surfaces rejected water but retained ink. The stone was then set within a press and when brought in contact with paper, it printed the paper with the inked image. Within fifty years of its first development, metal plates began to replace the limestone slabs. Today, rotary presses have replaced flatbed presses, paper and plastic plates are in use, and the use of color inks commonplace.
As lithography grew in sophistication, so did its varied uses. Originally a technique of printing, with time it grew into a popular medium for artists. Where the first images were created by hand, today the images can be created by one or more of a wide variety of techniques, e.g., photographic, chemical etching, computer-controlled optical scanning and engraving, digital art, and the like. Modern day lithographs are ubiquitous in the print and advertising industries, as well as many others.
Historically lithographs were two dimensional creations like any other picture or photograph. Perception of depth was dependent upon the content of the picture itself. However as described in U.S. Pat. No. 5,266,995 to Quadracci, et al., three dimensionality can be imparted to an image by first creating the image with a special stereoscopic camera and then overlaying the image with a lenticular lens sheet. Both the stereoscopic cameras and lenticular lens sheets are known in the art and are commercially available.
U.S. Pat. No. 5,113,213 to Sandor, et al. teaches a method of preparing three dimensional lithographs through the use and manipulation of computer images. In this technique, the images are interleaved into a predetermined number of planar images, and then printed with a high-resolution output imaging device on a spacer, and a selected edge of each interleaved image is aligned with a predetermined direction of the spacer.
However imparting the fourth dimension, motion, to a static picture remains absent in the art.